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Chinese Journal of Polymer Science 2020年第11期38卷 1258-1266,I0009页

作者： xi-ting lei Li-Fen Tong Ming-Zhen Xu Yong You xiao-Bo Liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Low dielectric in terlayer films have become an important element to ensure the development of the microelectr onics industry.A kind of flexible interlayer dielectrics,polyarylene ether nitrile/bisphenol A cyanate ester(PEN/BADCy)film,with good thermal stability and low frequency dependence,has been developed by solution casting ***,materials were designed to incorporate bisphenol A cyanate ester as a part of blend,contributing to the frequency stability and structural *** morphological study combined with electron microscopy revealed the uniform and flexible microstructure information with controllable morphology through self-polymerization of cyanate esters with different prepolymerization time and curing *** dielectric films could present high thermal stability with Tg>180℃.Significant improvement in the dielectric properties was achieved for the dielectric constant and loss was much stabler than neat PEN over the frequency range from 100 Hz to 5 *** the prepolymerization time was 3h and final curing temperature reached 230℃,the dielectric constant and dielectric loss of the films were 3.36 and 0.013 at 100 kHz,*** dimensional stability(CTE=53.67×10^-6 K^-1)was confirmed and con sidered beneficial to use as an in terlayer dielectrics.

关键词： Polyarylene ether nitrile Bisphenol A cyanate ester Interlayer dielectrics Tunable microstructures

The Role of Underlying Boundary Forcing in Shaping the Recent Decadal Change of Persistent Anomalous Activity over the Ural Mountains

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Advances in Atmospheric Sciences 2024年第8期41卷 1496-1510,1661-1667页

作者： ting lei Shuanglin LI Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Beijing Meteorological Service Center Beijing 100089China University of Chinese Academy of Sciences Beijing 100049China Department of Atmospheric Science China University of GeosciencesWuhan 430074China

Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variations are related to a large-scale circulation shift over the Eurasian Continent. The effects of underlying sea ice and sea surface temperature(SST) anomalies on the Ural PAE and the related atmospheric circulation were explored by Atmospheric Model Intercomparison Project(AMIP) experiments from the Coupled Model Intercomparison Project Phase 6 and by sensitivity experiments using the Atmospheric General Circulation Model(AGCM). The AMIP experiment results suggest that the underlying sea ice and SST anomalies play important roles. The individual contributions of sea ice loss in the Barents-Kara Seas and the SST anomalies linked to the phase transition of the Pacific Decadal Oscillation(PDO) and Atlantic Multidecadal Oscillation(AMO) are further investigated by AGCM sensitivity experiments isolating the respective *** sea ice decline in Barents-Kara Seas triggers an atmospheric wave train over the Eurasian mid-to-high latitudes with positive anomalies over the Urals, favoring the occurrence of Ural PAEs. The shift in the PDO to its negative phase triggers a wave train propagating downstream from the North Pacific. One positive anomaly lobe of the wave train is located over the Ural Mountains and increases the PAE there. The negative-to-positive transition of the AMO phase since the late-1990s causes positive 500-h Pa height anomalies south of the Ural Mountains, which promote a southward shift of Ural PAE.

关键词： Ural persistent anomaly Pacific decadal oscillation Atlantic multidecadal oscillation sea ice loss in Barents-Kara Seas

Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： Xue-Qing Wang Cheng Song ting lei Key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： lei Wan Yizhou Tong xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

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Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers

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Journal of Integrative Agriculture 2024年第4期23卷 1329-1337页

作者： Kaiwen lei Hao Wu Jerry W Spears xi Lin xi Wang Xue Bai Yanling Huang Key Laboratory of Animal Science of State Ethnic Affairs Commission Southwest Minzu UniversityChengdu 610041China Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization Southwest Minzu UniversityChengdu 610041China Department of Animal Science North Carolina State UniversityRaleighNC 27695-7621USA

This study aimed to investigate the dose-effect of iron on growth performance,antioxidant *** morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per *** dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)*** with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(Pxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein.

关键词： iron yellow-feathered broiler antioxidant function intestinal morphology tight junction protein

Immune regulation of the gut-brain axis and lung-brain axis involved in ischemic stroke

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Neural Regeneration Research 2024年第3期19卷 519-528页

作者： xiaodi xie lei Wang Shanshan Dong ShanChun Ge ting Zhu Institute of Neuroregeneration&Neurorehabilitation Department of PathophysiologySchool of Basic MedicineQingdao UniversityQingdaoShandong ProvinceChina School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjingJiangsu ProvinceChina Department of Rehabilitation Medicine The Affiliated Hospital of Qingdao UniversityQingdaoShandong ProvinceChina

Local ischemia often causes a series of inflammatory reactions when both brain immune cells and the peripheral immune response are *** the human body,the gut and lung are regarded as the key reactional targets that are initiated by brain ischemic *** microorganisms play an important role in immune regulation and metabolism and affect blood-brain barrier *** addition to the relationship between peripheral organs and central areas and the intestine and lung also interact among each ***,we review the molecular and cellular immune mechanisms involved in the pathways of inflammation across the gut-brain axis and lung-brain *** found that abnormal intestinal flora,the intestinal microenvironment,lung infection,chronic diseases,and mechanical ventilation can worsen the outcome of ischemic *** review also introduces the influence of the brain on the gut and lungs after stroke,highlighting the bidirectional feedback effect among the gut,lungs,and brain.

关键词： enteric glia cells gut microbiota gut-brain axis immune response inflammation ischemic stroke lung-brain axis microglia

An efficient schedulability analysis based on worst-case interference time for real-time systems

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Science China(Information Sciences) 2024年第09期67卷 88-104页

作者： Hongbiao LIU Mengfei YANG lei QIAO xi CHEN Jian GONG School of Computer Science and Technology Xidian University China Academy of Space Technology Beijing Institute of Control Engineering

Real-time systems are widely implemented in the Internet of Things(IoT) and safety-critical systems, both of which have generated enormous social value. Aiming at the classic schedulability analysis problem in real-time systems, we proposed an exact Boolean analysis based on interference(EBAI) for schedulability analysis in real-time systems. EBAI is based on worst-case interference time(WCIT), which considers both the release jitter and blocking time of the task. We improved the efficiency of the three existing tests and provided a comprehensive summary of related research results in the field. Abundant experiments were conducted to compare EBAI with other related results. Our evaluation showed that in certain cases, the runtime gain achieved using our analysis method may exceed 73% compared to the stateof-the-art schedulability test. Furthermore, the benefits obtained from our tests grew with the number of tasks, reaching a level suitable for practical application. EBAI is oriented to the five-tuple real-time task model with stronger expression ability and possesses a low runtime overhead. These characteristics make it applicable in various real-time systems such as spacecraft, autonomous vehicles, industrial robots, and traffic command systems.

关键词： five-tuple real-time task model real-time system spacecraft Internet of Things exact schedulability analysis worst-case interference time

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Multi-objective optimal control of tungiasis diseases with terminal demands

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International Journal of Biomathematics 2024年第3期17卷 123-151页

作者： Wei Lv Si-ting Zhang lei Wang Department of Mathematics Shanghai University Shanghai200444P.R.China Key Laboratory for Computational Mathematics and Data Intelligence of Liaoning Province Dalian University of Technology Dalian 116024P.R.China Department of Mathematics School of Science Shihezi UniversityShihezi 832003P.R.China

In this paper,we aim to minimize the epidemic size of tungiasis disease and economic costs simultaneously,with terminal demands for infected humans.A human-jigger parasite control system with four control schemes for humans and jiggers is *** propose a multi-objective optimal control problem with terminal constraints,in which the accumulated number of infected humans and control costs are *** applying the modified normal boundary intersection algorithm and the interior point scheme,numerical simulations for different combinations of control schemes are carried out,and actual data in Madagascar are *** combination schemes are indicated from the perspectives of disease eradication,cost saving and time *** these effective combinations are properly performed,the disease can be *** only minimizing the epidemic size,the combination of the optimal treatments and adulticiding efforts is the best choice in the rainy season;the combination of the optimal personal protections and treatments is the preferential option in the dry *** only minimizing the economical cost,the combination of the optimal adulticide and larvicide is the better selection in the rainy season;the combination of the optimal personal protections,treatments and adulticiding efforts is the prior choose in the dry ***,there is a trade-off between the two objectives for all the effective combinations,decision-makers may choose an appropriate one to control the disease.

关键词： Multi-objective optimal control terminal demand control combination tun-giasis disease

Inter-stage performance and energy characteristics analysis of electric submersible pump based on entropy production theory

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Petroleum Science 2024年第2期21卷 1354-1368页

作者： Hui Wang Yang Yang Bin xi Wei-Dong Shi Chuan Wang lei-lei Ji xiang-Yu Song Zhao-Ming He College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou225009JiangsuChina College of Electrical and Mechanical Engineering Nanchang Institute of TechnologyNanchang330044JiangxiChina College of Mechanical Engineering Nantong UniversityNantong226019JiangsuChina National Research Center of Pumps Jiangsu UniversityZhenjiang212013JiangsuChina Zhejiang Zhenxing Petrochemical Machinery Co. Ltd.Ruian325204ZhejiangChina Department of Mechanical Engineering of Texas Tech University Lubbock79411TXUSA

The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction *** lifting capacity is enhanced by the multi-stage tandem structure, but variations in energy characteristics and internal flow across stages are also introduced. In this study, the inter-stage variability of energy characteristics in ESP hydraulic systems is investigated through entropy production(EP) analysis,which incorporates numerical simulations and experimental validation. The EP theory facilitates the quantification of energy loss in each computational subdomain at all ESP stages, establishing a correlation between microscopic flow structure and energy dissipation within the system. Furthermore, the underlying causes of inter-stage variability in ESP hydraulic systems are examined, and the advantages and disadvantages of applying the EP theory in this context are evaluated. Consistent energy characteristics within the ESP, aligned with the distribution of internal flow structure, are provided by the EP theory, as demonstrated by our results. The EP theory also enables the quantitative analysis of internal flow losses and complements existing performance analysis methods to map the internal flow structure to hydraulic losses. Nonetheless, an inconsistency between the energy characterization based on EP theory and the traditional efficiency index when reflecting inter-stage differences is identified. This inconsistency arises from the exclusive focus of the EP theory on flow losses within the flow field, disregarding the quantification of external energy input to the flow field. This study provides a reference for the optimization of EP theory in rotating machinery while deeply investigating the energy dissipation characteristics of multistage hydraulic system, which has certain theoretical and practical significance.

关键词： Electric submersible pump(ESP) Entropy production theory Energy characteristics Inter-stage differences

Double-ring high-frequency common-mode switching oscillation current sensor for inverter-fed machine winding insulation monitoring

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Global Energy Interconnection 2024年第1期7卷 106-116页

作者： Lingqing Pan xizhou Du xing lei ting Ye Dawei xiang Hao Li College of Electrical Power Engineering Shanghai University of Electric PowerShanghai 200090P.R.China State Grid Shanghai Municipal Electric Power Company Shanghai 200122P.R.China College of Electronics and Information Engineering Tongji UniversityShanghai 201804P.R.China

Insulation failure significantly contributes to the unpredictable shutdown of power *** to the partial discharge and high-frequency(HF)injection methods,the HF common-mode(CM)leakage current method offers a non-intrusive and highly sensitive ***,the detection of HF CM currents is susceptible to interference from differential-mode(DM)currents,which exhibit high-amplitude and multifrequency components during normal *** address this challenge,this paper proposes a double-ring current sensor based on the principle of magnetic shielding for inverter-fed machine winding insulation *** inner ring harnesses the magnetic aggregation effect to isolate the DM current magnetic field,whereas the outer ring serves as the magnetic core of the Rogowski current sensor,enabling HF CM current ***,the magnetic field distributions of the CM and DM currents were ***,a correlation between the sensor parameters and signal-to-noise ratio of the target HF CM current was ***,an experimental study was conducted on a 3-kW PMSM for *** results indicate that the proposed double-ring HF CM sensor can effectively mitigate DM current *** to a single-ring sensor,a reduction of approximately 40%in the DM component was achieved,which significantly enhanced the precision of online insulation monitoring.

关键词： Magnetic shielding Double-ring Common-mode current Maxwell simulation